Attorney General Loretta E. Lynch has decided to launch a federal investigation into whether the Baltimore Police Department has engaged in a “pattern or practice” of excessive force.

Lynch’s announcement about the Justice Department’s probe — the latest in a string of municipalities that are being investigated by the federal government for civil rights violations — could come as early as Friday, according to two law enforcement officials.

A Justice Department spokeswoman declined to comment Thursday night.

Lynch hinted Thursday that a decision could come soon, when she testified during her first hearing on Capitol Hill as attorney general. She said that she would decide “in the coming days” whether to have the department’s civil rights division open an investigation into the Baltimore police force. Baltimore Mayor Stephanie Rawlings-Blake on Wednesday called on the Justice Department to open a federal investigation.